Vortex linkages

ABSTRACT

There is disclosed a manipulative toy in the form of a linkage containing an even number of at least six links, each of which links comprises a central limb with two end limbs projecting one from each end thereof in planes mutually perpendicular to one another, each end limb of each link being journalled alongside an end limb of an adjacent link so as to pivot generally coaxially therewith and enable the linkage to be successively turned inside out through a position in which it defines a planar polygon, in which position half the journalled pairs of limbs stand perpendicular to the plane of the polygon at each vertex thereof whilst the remaining journalled pairs of limbs lie in the plane of the polygon and project from the mid points of the sides of the polygon towards the centre thereof.

United States Patent Flowerday Nov. 4, 1975 VORTEX LINKAGES PrimaryExaminer-Hugh R. Chamblee 76 I t I F d k Geo Fl d 42 AssistantExaminer-Robert F. Cutting 1 nven or a t E i g ggrg 3 OH] Attorney,Agent, or FirmEdward F. Connors England [22] Filed: Aug. 12, 1974 [57]ABSTRACT PP 496,881 There is disclosed a manipulative toy in the form ofa linkage containing an even number of at least six links, each of whichlinks comprises a central limb with two [30] Fgrelgn Apphfahonrnonty tend limbs projecting one from each end thereof in Aug. 3, 1973 UnitedKmgdom 39910/73 planes mutually perpendicular to one another, each endlimb of each link being journalled alongside an 5% 8 46/1 iz f gg gg endlimb of an adjacent link so as to pivot generally d 27 28 coaxiallytherewith and enable the linkage to be suc- 1 1e 0 arc 3 cessivelyturned inside out through a position in which it defines a planarpolygon, in which position half the journalled pairs of limbs standperpendicular to the [56] References cued plane of the polygon at eachvertex thereof whilst the UNITED STATES PATENTS remaining journalledpairs of limbs lie in the plane of 1,853,436 4/1932 Krause 273/155 thepolygon and project from the mid points of the 2,959,888 1 1/ 1960 Noblei 46/28 sides of the polygon towards the centre thereof. 3,546,04912/1970 Kostich 46/28 10 Claims, 6 Drawing Figures re 2 t Sheet 2 of 33,916,559

US. Patent Nov. 4, 1975 US. Patent Nov. 4, 1975 Sheet 3 of3 3,916,559

VORTEX LINKAGES FIELD OF THE INVENTION The invention relates tomanipulative toys.

SUMMARY OF THE INVENTION The invention provides a manipulative toy inthe form of a closed linkage containing an even number of at least sixlinks, each of which links comprises a central limb with, at each endthereof, two end limbs projecting from the central limb in planesmutually perpendicular to one another, each end limb of each link beingjournalled alongside an end limb of an adjacent link so as to pivotgenerally coaxially therewith and en able the linkage to be successivelyturned inside out through a position in which it defines a planarpolygon, in which position half the journalled pairs of limbs standperpendicular to the plane of the polygon at each vertex thereof whilstthe remaining journalled pairs of limbs lie in the plane of the polygonand project from the mid points of the sides of the polygon towards thecentre thereof.

The end limbs may be journalled in surrounding tubes.

Said tubes may be constituted by helically coiled wire.

The tubes may be attached to or form part of either of the end limbs ofeach journalled pair.

Alternatively the end limbs may be press fitted into the tubes and thelinkage held together by friction between the press fitted parts.

The links may be comprised of wire rods.

Alternatively the links may be comprised of rods of a plastics material.

The pivoted pairs of limbs may be permanently journalled together.

For example, they may be so journalled by a flexible connectingmembrane.

When the limbs are permanently journalled together, the linkage may bemoulded or fabricated in one piece from a material of sufficientinherent flexibility to permit each journalled pair of end limbs tocomprise a single resiliently flexible member.

BRIEF DESCRIPTION OF THE DRAWINGS Examples of the invention will now bedescribed with reference to the accompanying drawings, in which:

FIGS. II and 2 show a plan view of a continuous ring of members inalternative closed and open positions respectively;

FIG. 3 shows a single skewed quadrilateral for the continuous ring ofmembers shown in FIGS. 1 and 2;

FIG. 4 shows an alternative single skewed quadrilateral formed from acontinuous wire coil with straight extensions bent to fit into the coilof an adjacent similar member;

FIG. 5 shows a perspective view of a continuous ring of membersconforming to a square; and

FIG. 6 shows a perspective view of a continuous ring of members in theform of a mobius strip.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIGS. 1, 2 and 3 acontinuous ring of members in which the inner sides form a triangle isshown as an example. Common edges 1, 2, 3, 4, 5 and 6 are constructedfrom tubes. In the plan view shown in FIG. 1, the longitudinal axes ofthe tubes 1, 2 and 3 are lying in the plane of the paper and thelongitudinal axes of the tubes 4, 5 and 6 extend outwards towards thereader at right angles to and from the plane of the paper. Inalternative embodiments the longitudinal axis of one of the tubes 4, 5,or 6 may extend in the opposite direction, i.e. into the paper from theplane of the paper. Inner edges 7, 8, 9, 10, l1 and 12 form a trianglefrom the upstanding tubes or common edges 4, 5 and 6. The inner edgesextend at right angles from one end of the tubes 1, 2 and 3 to the endof the tubes 4, 5 and 6 lying in the plane of the paper. The outer edgesl3, 14, 15, I6, 17 and 18 extend from opposing ends of the tubes 1, 2,3, 4, 5 and 6 to which the inner edges are inserted. The inner edges 7,8, 9, l0, l1 and 12 are constructed from wire oflength 3 plus thelengths of extensions at right angles for insertion into the pivotaltubes, the same length as the tubes although this is not essential. Theouter sides 13, 14, 15, 16, 17 and 18 are constructed from wire oflength 5 plus lengths for insertion into tubes. The tubes allow pivotalmovement and the whole continuous ring of members can be rotated byhand.

The inside tube diameter should allow a close fit for the wires makingup the inner and outer sides as shown in FIG. 1. In the case of FIG. 1the inside tube diameter should be about 2 l)d (where d is the wirediameter) to allow a close but easy fit of four wires in a tube. Eachinner and outer edge formed by a wire, at a distance of one unit tubelength from each end, is bent in perpendicular planes. The short wires,the inner sides, are bent to an angle of ninety degrees, three to theleft and three to the right. The long wires, the outer sides, aresimilarly bent to an angle of, substantially sixtythree degrees, threeto the right and three to the left.

To this basic linkage may also be added the other two sets of wirequadrilateral edges, namely: the 6 which approximate the lines from thecentre of the triangle to its vertices, and the 6 which approximate thelines from the top of the vertical tubes forming the common edges to themid points of the triangle sides. This is shown by the peeked and dashedlinesin FIG. 2.

To make a ring of continuous members as shown in FIG. 1, the wiresforming the inner and outer edges 7 to 18 are taken in pairs, one longand one short of the same parity and are arranged into six quadrilateralforms, three with rightand three with left-handed twist. These skewquadrilaterals are placed alternately left-right-left-right-left-rightin a ring and are joined by tubes 1 to 6 slipped over the ends of thewires. This can be done so that one end of each tube receives two longwires of opposite parity and that the other end of each tube receivestwo short wires of opposite parity. If this is done it will be seen thatthe linkage maintains its assembly yet is free to be turned successivelyinside out.

For a wire to disengage from a tube it must rotate on the axis of anadjacent hinge but is restrained from doing so by the fixed position ofthe first tube. A spring coil of wire might be used instead of tubing.The coil can be closely set in internal diameter to make a smoothlyworking hinge that does not tend to come apart.

In an alternative embodiment shown in FIG. 4, the ring of members may beconstructed from a number of torsion springs 40 as one common edge withstraight end pieces 41 and 42 to form the inner and outer edgesextending at fixed angles from the coil axis. The ends 43 and 44 of theinner and outer sides, are bent to fit into the torsion spring 40 of thenext member thus providing a pivotal link.

It will be noted that a continuous ring of members is related to aregular plane polygon as shown in FIG. 1. It will be seen that one setof adjacent edges of unit length stand perpendicular to the plane ateach vertex of the polygon. The other set of common adjacent edges liein the plane of the polygon and approximate the lines from the centre ofthe figure to the mid points at the sides of it. One group of straightwire extensions lie in the polygonal plane and are equal to one half ofa polygon side and make angles of ninety degrees with the common edgefrom which they extend, and an angle of ninety degrees with the commonedge into which their extremities are engaged. With the common edge asunit length, the length of these extensions is equivalent to (tan A+2)where A 360/2N and where (+2) accounts for the hinge. (In the examplepreviously described where the members resemble torsion springs, (+1)accounts for insertion in a hinge).

Another group of edges, i.e. those extending from the opposite ends ofthe adjacent members approximate the hypotenuse from the centre of thepolygon to the top of a vertical common edge. It will be apparent thatwith the vertical edges as one unit, the length of these extensions isequivalent to tan A+2 +2) and that these extensions leave and engage thehinges at an angle B where TanB equals secA. At unit distance from theirends, these outer edges are bent at the appropriate angle to accommodatethe common edge of the adjacent member, which accounts for the (+2). Twoother sets of wire forms may be added to those mentioned. Those whichapproximate the lines from the top of vertical common edges to the midpoints of the sides of the polygon; and those which approximate thelines from the centre of the polygon to its vertices. These four sets ofwire forms may be used in different combinations throughout the linkage.

The continuous rings of members discussed so far as examples, have beenbased on the equilateral triangle as shown in FIGS. 1 and 2. They canhowever be made to any triangle provided that the common sides standingat the vertices of one closed triangular position are correctlyproportional in length to allow the passage of the top vertex pointsthrough both closed triangular positions. In the case of the equilateraltriangle and other regular polygons all common edges are equal.

A continuous ring of members can be based on other plane polygons, and,as in the case of the triangle, these can be regular or irregular.

FIG. 5 shows a square based continuous ring of members with two oppositecommon sides 51, 52 reversed in respect to the remaining two sides 53and 54. This variation may be used with a continuous ring of members ofcertain other geometries and periodicities.

A continuous ring of members is related to a plane polygon as previouslydescribed. It may be based on a polygon of any number of sides, but thelarger number of sides the great flexibility of the continuous ring ofmembers.

FIG. 6 shows a further example which can be seen to correspond to amobius strip and is derived from the quadrilateral form shown in FIG. 2.

In addition to skewed quadrilaterals which have a generally rectilinearnature, by interconnecting each end of each common edge to each end ofan adjacent common edge it can be seen that there is a framework of agenerally solid shape formed. Thus, a solid continuous ring of memberscan be formed by producing in one piece a moulding using a materialwhich would be sufficiently flexible to act as a hinge in thin sectioncorresponding to the common edges of adjacent skewed quadrilaterals.

All the continuous rings of members as described previously can be madefrom wire or other material. For example the inner and outer edges maybe wire pieces inserted into metal or plastic tubes. However the tubescan be formed as previously described, by a coil spring, or by any otherdevice which functions as a pivotal restraint.

I claim 1. A manipulative toy in the form of a closed linkage containingan even number of at least six links, each of which links comprises acentral limb with two end limbs projecting one from each end thereof inplanes mutually perpendicular to one another, means pivotally joiningsaid links such that each end limb of each said link is journalledalongside an end limb of an adjacent one of said links so that mutuallyadjacent links pivot generally coaxially with respect to one another andenable the linkage to be successively turned inside out through aposition in which it defines a planar polygon, in which position halfthe journalled pairs of limbs stand perpendicular to the plane of thepolygon at each vertex thereof whilst the remaining journalled pairs oflimbs lie in the plane of the polygon and project from the mid points ofthe sides of the polygon towards the centre thereof.

2. A manipulative toy according to claim 1 in which the end limbs arejournalled in surrounding tubes.

3. A manipulative toy according to claim 2 in which the tubes comprisehelically coiled wire.

4. A manipulative toy according to claim 2 in which the tubes form partof an end limb.

5. A manipulative toy according to claim 2 in which the end limbs arepress fitted into the tubes and the linkage is held together by frictionbetween the press fitted parts.

6. A manipulative toy according to claim 1 in which the linkage iscomprised of wire rods.

7. A manipulative toy according to claim 1 in which the links compriserods of a plastics material.

8. A manipulative toy according to claim 1 in which the pivoted pairs oflimbs are permanently journalled together.

9. A manipulative toy according to claim 8 in which the pivoted pairs oflimbs are journalled together by a flexible connecting membrane.

10. A manipulative toy according to claim 8 in which the linkage isfabricated in one piece from a material of sufficient inherentflexibility to permit each journalled pair of end limbs to comprise asingle resiliently flexible member.

1. A maNipulative toy in the form of a closed linkage containing an even number of at least six links, each of which links comprises a central limb with two end limbs projecting one from each end thereof in planes mutually perpendicular to one another, means pivotally joining said links such that each end limb of each said link is journalled alongside an end limb of an adjacent one of said links so that mutually adjacent links pivot generally coaxially with respect to one another and enable the linkage to be successively turned inside out through a position in which it defines a planar polygon, in which position half the journalled pairs of limbs stand perpendicular to the plane of the polygon at each vertex thereof whilst the remaining journalled pairs of limbs lie in the plane of the polygon and project from the mid points of the sides of the polygon towards the centre thereof.
 2. A manipulative toy according to claim 1 in which the end limbs are journalled in surrounding tubes.
 3. A manipulative toy according to claim 2 in which the tubes comprise helically coiled wire.
 4. A manipulative toy according to claim 2 in which the tubes form part of an end limb.
 5. A manipulative toy according to claim 2 in which the end limbs are press fitted into the tubes and the linkage is held together by friction between the press fitted parts.
 6. A manipulative toy according to claim 1 in which the linkage is comprised of wire rods.
 7. A manipulative toy according to claim 1 in which the links comprise rods of a plastics material.
 8. A manipulative toy according to claim 1 in which the pivoted pairs of limbs are permanently journalled together.
 9. A manipulative toy according to claim 8 in which the pivoted pairs of limbs are journalled together by a flexible connecting membrane.
 10. A manipulative toy according to claim 8 in which the linkage is fabricated in one piece from a material of sufficient inherent flexibility to permit each journalled pair of end limbs to comprise a single resiliently flexible member. 